1. Field of the Invention
The present invention relates to a ceramic material for injection molding, and a method of injection molding using the material.
2. Related Art Statement
Heretofore, injection molding has been known as a method of producing ceramic molded bodies of relatively complicated configurations. In this method, a ceramic powder and an organic binder consisting of a resin like polyethylene, or polystyrene, etc., and a wax, are mixed, injected and filled in a die, and formed to obtain a shaped body. The shaped body is subsequently heated (degreased) to burn and remove the organic binder, and then fired to produce a sintered body.
In the injection molding method, usually a mixture of raw materials is heated to above a plasticizing temperature thereof, for example about 120.degree.-160.degree. C., injected and filled in a die of about 120.degree.-160.degree. C., cooled and solidified, and then removed from the die to obtain a shaped body.
However, in the usual injection molding method, the mixture of raw materials and the die have different temperatures at the time of injection molding, so that there are drawbacks in that the injected mixture loses its fluidity rapidly in the die to yield molding defects like reclining or recess at the molded surface due to molding of insufficient filling of the mixture, and strain in the molded body due to inhomogeneous filling of the mixture which causes cracks at the time of degreasing.
In order to solve the above drawbacks, the inventors researched and experimented and discovered to the present invention, which includes a method of injection molding which minimizes temperature difference between the molding material and injection die, and a molding material suitable for the injection molding.